


Repeat

by animatedrose



Category: Undertale (Video Game)
Genre: Alternate Universe - Underswap, Chara gets back at Sans in the worst way ever, Chara treated as an "it", Death, Genocide Run, Judgment Hall, Papyrus dies a lot, Poor Sans, Revenge, Sansloid video, Snowdin, Sorry Not Sorry, Underswap at end, expect much sadness, gender neutral chara, jubyphonic - Freeform, kagerou days, reset, will be confusing for anyone not familiar with the Genocide run final fight
Language: English
Status: Completed
Published: 2016-06-04
Updated: 2016-06-11
Packaged: 2018-07-12 06:00:57
Rating: Teen And Up Audiences
Warnings: Major Character Death
Chapters: 4
Words: 2,896
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/7088119
Author URL: https://archiveofourown.org/users/animatedrose/pseuds/animatedrose
Summary: <blockquote class="userstuff">
              <p>Sans has dreams a lot lately. Of a kid with a knife and red eyes wiping out the underground and killing his brother. The same kid that Papyrus is intent on befriending.</p><p>But they're not dreams. This is reality. A loop of constant revenge against Sans for a timeline he can barely even remember. A forced repeat of the one time during the child's rampage that effectively broke him of hope. And there is no escape.</p><p>Or is there?</p>
            </blockquote>





	1. Beginning

**Author's Note:**

> Inspired by both the video Kagerou Days by JubyPhonic, as well as the Undertale version by Sansloid. Both can be found on Youtube at the following links:
> 
> https://www.youtube.com/watch?v=MU-rdG-M5Ho – original version
> 
> https://www.youtube.com/watch?v=aazocVw3fh4 – Undertale version
> 
> The ending was inspired by a comment in the Sansloid video. Thanks for that, dude…

_Dust… So much dust…_

_Papyrus…_

_Why?_

_Why couldn’t I—_

**BEEP BEEP BEEP!!**

Sans jolted, sockets snapping open in shock. The dream was cast into oblivion as the beeping of his cell phone alarm dragged him to wakefulness.

The skeleton groaned, arm over his skull, trying to ignore the sound.

…Nope, there was no ignoring it…

Sans rose and grabbed the phone, shutting off the alarm. It was 12:30, past noon. Not his greatest sleep record ever but hey, it was pretty good.

“SANS! GET UP! YOU HAVE SENTRY DUTY TODAY!”

And there was Papyrus, shouting up a storm again. Sans eyed the trash tornado in his room with humor. Storms. Heh.

“SANS!!”

“i’m coming, bro,” Sans called, rolling out of bed to pull on his coat and slippers.

“THEN COME FASTER!!”

…There were so many awful things he could joke about with that, but they’d all go over Papyrus’ skull.

Sans filed those away and left his room to join his taller sibling downstairs. Papyrus, decked out in his battle body and scarf, was ready for his daily patrol. Funny how that uniform was originally just a costume. It fit, though. Papyrus wouldn’t look like himself if he wasn’t wearing it.

“okay, i’m up, bro,” Sans said, yawning for effect.

“GOOD! WE HAVE PATROLLING AND HUMAN SEARCHING AND ROYAL GUARDING TO DO! AND I, THE GREAT PAPYRUS, WILL NOT BE MADE LATE BECAUSE YOU WANTED TO SLEEP IN!”

Sans snickered at Papyrus, strutting about and posing. The daily routine for “the great Papyrus”. His bro was funny, amusing as hell, even if Papyrus hated it. The other wanted to be taken seriously so badly.

They left the house and trudged across Snowdin and the surrounding forest, the newly-fallen snow leaving clear footprints behind them as they walked. The breeze was chilly—how was there even a breeze underground?—but Sans didn’t mind it. It went right through him, after all.

…Heh. Get it? ‘Cause he was a skeleton.

“HUMAN! YOU ARE UP BRIGHT AND EARLY! JUST WHAT I EXPECT!”

Sans snapped back to awareness. Oh yeah, there was a human here.

No, _the_ human. The one from yesterday, that ignored or went around all of Papyrus’ puzzles. A little kid with brown hair and a blue and pink striped shirt.

The one with murder in its eyes. The one that sent shivers through Sans’ bones. The one that looked too familiar for words but Sans couldn’t put his phalange on why.

Sans slipped behind his sentry station, leaning on the counter to stare at the dark sky…ceiling. Kinda hard to see the ceiling during the day. Was it really day?

Underground physics were strange.

“OKAY, HUMAN! YOU’D BEST HIDE! I’LL TALK TO YOU LATER!”

The human gave no wave, no kind of goodbye at all, as it headed toward Snowdin. Papyrus smiled widely, laughing. Sans couldn’t help but tiredly smile too. If his bro was happy, so was he.

Even if the reason was rather creepy. Sans certainly noticed the lack of life in the forest on their way over. It put him on edge. It was like in his dreams. Everyone always said humans were dangerous but…it was so tiny, just a child.

“BROTHER!”

“huh?” Sans snapped to attention instantly. “yeah, bro?”

“I’VE DECIDED TO MAKE FRIENDS WITH THE HUMAN!”

“you have? why, bro?”

“BECAUSE…THE HUMAN LOOKS SO LONELY. IT WON’T DO PUZZLES OR SMILE AT ME. SO I’VE DECIDED! IF I SHOW IT KINDNESS RATHER THAN VIOLENCE, AS I MUST IF WE FOUGHT, PERHAPS WE CAN BE FRIENDS! AFTER ALL, I THINK EVERYONE DESERVES A FRIEND. PERHAPS THEN THE HUMAN WILL BE MORE FRIENDLY TOWARD US.”

Sans smiled. “that’s a great plan, bro. never would’ve thought of it myself.”

If anyone could get that human to stop being so cold, it was his bro. Papyrus could make friends with anyone, even Undyne. Sans couldn’t help but be proud of his little bro for his persistence.

“THEN MAYBE YOU SHOULD DO MORE THINKING, BROTHER.”

“hey, I put a skele-ton of time into thinking.”

“SANS!!”

Sans just grinned. He knew Papyrus was smiling. Papyrus always smiled at his jokes and puns. Always.

“I’VE HAD ENOUGH! I’M GOING TO BEFRIEND THE HUMAN!”

“good luck, bro.”

Papyrus turned, racing away across the snow with a loud cackle of “NEY HEH HEH!” trailing after him.

Sans smiled, resting his skull on the counter of his station. Maybe he could catch some sleep now while his bro was away.

Papyrus was persistent. He could definitely get the kid to change, no doubts. There was nobody in the whole Underground that was immune to Papyrus’ friendly demeanor. There would be nothing to worry about.

…

Right?

…

Wouldn’t hurt to go watch. Just in case.

Besides, what if Undyne turned up? Didn’t want a bloodbath happening with his bro so close.

Sans sat up, stretching his bones, before taking a shortcut. Turning the corner near Grillby’s, he took a second shortcut and ended up just outside of Snowdin. He scanned the snow as he crunched along. They couldn’t be too far away.

Oh, there they were!

Papyrus was standing in the open, arms outstretched, exclaiming about friendship. Typical Papyrus. Sans smiled. Why had he been so…wor…ried…?

…

Why did the human have a knife?

…

Did the kid have a knife earlier? Sans didn’t see it before. Had it just picked it up? From where? Nobody the short skeleton knew just left knives lying around.

The kid was smiling, but it wasn’t friendly. Papyrus stepped closer, looking nervous but determined. He would win over this human. He had to!

“pap!” Sans cried, dashing toward them.

The human slashed their knife, cut through Papyrus’ armor. A second slash disconnected the taller skeleton’s head, sending it crashing in the snow.

“PAP!!” Sans howled, his voice—along with his hope—lost in a sudden roar of wind.

Papyrus turned to dust, leaving his red scarf and a pile of fine dust behind. The dust scattered in the wind. Sans stumbled forward, sockets dark except for tiny pinpricks of light. He crashed to his knees by the tattered scarf.

“papyrus.”

Words—promises, compliments, encouragements—flooded his head. They all came crashing down on him as he stared at the remains of his sibling. Just like in his dreams.

…But they weren’t dreams…were they?

_“don’t worry, bro. you’ll be fine, nobody will hurt you.”_

_“you can befriend anyone. who wouldn’t want a cool friend like you, bro?”_

_“that’s a great plan, bro. never would’ve thought of it myself.”_

_“there’s nothing a super cool guy like yourself can’t do, bro.”_

A giggle reached his ears. The child stood there, dust-coated knife in hand. Their smile was twisted, eyes the color of blood.

“In this cruel world, there are only two choices—kill or be killed.”

Snow was falling again, covering the scene up. Like nothing had happened. As if Papyrus hadn’t just died.

 _That isn’t fair! You can’t just forget him like this!_ Sans wanted to scream those words to the sky.

The child was laughing. Sans glared, left eye turning blue. Magic licked at his soul, screaming for release.

That’s when the next RESET happened.

Sans wasn’t sure whether to call it a miracle or a curse, considering what was to come.


	2. Middle

**Notes for the Chapter:**

> Ugh... This was supposed to be uploaded day after day because I have the story completed, but I got so busy. Try to upload remaining chapters right away now so I'm not leaving you waiting. Sorry...

Clocks ticked in his head as Sans opened his eyes. He was in his room again. His cell phone alarm wasn’t going off.

He rolled out of bed, pulling his coat and slippers on. Then he checked his phone. Just after noon. The date was the same as…

_Papyrus going to befriend the human. The knife. Dust. Kill or be killed._

Sans frowned. Coincidence. He just had another rotten dream, that’s all. Nothing to panic over.

The sky was dark. Snow was falling gently. It was just the same as every other day in Snowdin.

Then why was it so eerily similar to his dreams? Nightmares?

“SANS! GET UP! YOU HAVE SENTRY DUTY TODAY!”

Sans let out a breath he hadn’t realized he’d been holding. Papyrus was okay. Just a dream. Everything was fine.

He went through the usual motions that came with getting up. He wandered downstairs, had breakfast—Papyrus insisted it was lunchtime, NOT breakfast—and headed out to his sentry station near the ruins with his bro. The same things he did every day.

The same things he did in his dreams.

“—THINK EVERYONE DESERVES A FRIEND. PERHAPS THEN THE HUMAN WILL BE MORE FRIENDLY TOWARD US.”

Sans jolted at that. Wait! Had Papyrus just said what he’d thought Papyrus said? The same conversation from—

“SEE YOU LATER, BROT—”

“wait!”

Sans reached out, catching Papyrus’ elbow joint before the taller could dart away. He was nearly dragged over the counter of his station but Papyrus managed to stop before succeeding in that.

“uh… i got a better idea. i’m up for some of the exercise you do in the mornings. the, uh…”

“BUT THE HUMAN—”

“can wait until later. look at me, bro. i need the exercise. come on, humor me.”

This was stupid. He was letting some messed up dreams get the better of him. But…it had been so realistic. If anything ever happened to Papyrus, especially something like that, Sans would never forgive himself.

He was an older brother. Sue him for playing in his sibling’s best interest.

Even if it was fueled by dreams.

“YOU…REALLY WANT TO EXERCISE WITH ME?”

“yeah. sure. let’s just…wait on the human thing. they aren’t going anywhere.”

“…OKAY!!”

So they jogged. Well, Papyrus sprinted. Sans jogged at the start…and slowed to a crawl near the cliffs. Sweat ran down his skull.

 _maybe going for exercise as an excuse wasn’t smart. i’m out of shape,_ Sans decided, wheezing.

“SANS! LOOK!”

“huh?”

Sans looked up to see Papyrus up ahead. He was pointing excitedly at something. Sans pushed his legs to keep moving until he reached his sibling.

There was the table and the microwave and the plate of frozen spaghetti. All a distraction crafted by Papyrus for the human. A distraction that the human did not go for.

“THERE’S A NOTE! I BET IT’S FROM A FAN!” Papyrus declared, scooping up the plate and the sheet of paper tucked under it.

“sweet, bro. told you that you had some,” Sans smiled, wandering over to the unplugged microwave.

“OOOOH!! SANS, LISTEN! WHOEVER WROTE THIS IS VERY SWEET INDEED! I, THE GREAT PAPYRUS, AM SO VERY HAPPY!”

Sans smiled, fingering the chilly cord. “i bet, bro. told you that people loved you. you’re the coolest, after all.”

“LISTEN TO THIS!” Papyrus gushed, “ _DEAR THE GREAT PAPYRUS_ —THEY CALLED ME THE GREAT PAPYRUS!!— _I HAVE LEFT THIS SPAGHETTI FOR YOU AS A TOKEN OF OUR FRIENDSHIP. PLEASE ACCEPT IT. FORGIVE MY SHYNESS. I HOPE WE CAN BE THE CLOSEST OF FRIENDS ONE DAY. LOVE, A FAN._ DID YOU HEAR THAT, SANS? THEY PUT ‘LOVE’ AT THE END!”

“told you, bro. you got fans all ov—”

Sans turned to see a small frame dart from the trees. The glint of metal caught his eye first.

A knife. The human.

NO!

“pap—”

And just like that, in the span of a second, the one he treasured most was taken away…again.

Slashes and stabs tore through Papyrus’ battle body and scarf, exposing bones to be broken and dusted. The plate of spaghetti fell to the snow and the note was pulled away by the wind.

A trap. The kid set a trap! But how? What did they want with Papyrus? How did they know he’d bring Papyrus here?

…Unless the dream hadn’t been a dream…

Papyrus fell, reduced to dust once again. Red, glaring eyes smiled at the destruction. Sans froze before lunging. Maybe if he kept all the dust, Alphys could bring Papyrus back!

The child smiled, stepping in Sans’ path. Thrusting a hand forward, they caught Sans’ shirt collar and yanked him sideways. Sans coughed, trying to lurch away. He was too caught up in his disbelief that the kid’s words cut through him like a knife.

“You can’t escape this never-ending nightmare, Sans.”

Never ending? Then the dreams had been real?

Was this going to happen every time he woke up now? Was he going to have to watch Papyrus die every day? How? Why?

The child shoved Sans backward, sending the skeleton crashing into the snow. The world seemed to turn black around them. A glowing box appeared before the child. They pressed a hand to it.

“Let’s RESET and do this again! Just like at Judgment Hall! Only I’ll be winning, not you!”

Reset? Again? No!

Sans wasn’t going to let this happen again. Not this cruel fate. Not to Papyrus!

He’d stop this kid. Somehow. Someway. He’d save Papyrus. Save everyone!

Somehow…

Someday…


	3. End

**Notes for the Chapter:**

> Here's the third chapter for you. Just uploading them all right now so I don't procrastinate, whether by choice or force. Yeah...

How many times had he watched Papyrus die now? A hundred? A thousand? Ten thousand?

Sans didn’t know. He tried to keep count at first but lost it after thirteen or so. Then he tried to keep written records but those vanished with each RESET. The numbers blended together in his head.

But the memories didn’t. Each death stood out uniquely in his memory, too numerous to count.

It didn’t matter how much he tried to prevent it. No matter how far away he took Papyrus. What distractions he provided. The kid was always there, knife drawn, ready to kill the instant Sans wasn’t watching or was inattentive.

Every attempt led to a dead end. Why did Papyrus keep trying to befriend that kid? All the kid wanted was murder!

He was sick of this day, its gentle snowfall and dark sky. He hated it all. Winter. Snowdin. The kid.

But not Papyrus. He could never hate Papyrus. His brother’s persistence was why he loved him so much.

And that persistence was killing him now. Sans hated that.

He felt divided from himself, like he was watching a mirror image of himself trying to save Papyrus. He couldn’t interfere. When the kid arrived, it was all over. Papyrus died. The kid said something cruel, something snarky. Then they’d RESET and the day would begin anew.

Nobody remembered but Sans. Maybe the kid remembered. Papyrus didn’t.

Why?

…

It was happening again. He felt like he was in a glass box. He and Papyrus were in an open, snowy field outside of Snowdin. The spot where Papyrus had planned to befriend the kid. The scene of his very first death and countless deaths after that.

The child was charging, knife in hand, red eyes flashing. Papyrus still stood there, arms open, begging for mercy and friendship, unwilling to raise a hand against the kid that was clearly out to take his life. And here Sans stood, unable to move, separated from the scene by so much numbness.

The story would end the same way as it always did. Papyrus would die. The kid would laugh. RESET. Rinse and repeat into infinity.

…

It didn’t have to end the same way.

…

Today would be the last time Sans stood by. The last time he did nothing but run.

…

Today would be the end.

…

“SANS!”

Papyrus yelped as he was shoved backward to crash into the snow. A knife tore through blue wool and thick bone, slicing into the short skeleton before him.

Today, Sans would intervene. He would protect Papyrus from his fate. He’d die today instead. Maybe that would sate this stupid kid.

The knife sank deep. His 1HP dissolved. His body was rapidly becoming dust.

“SANS!” Papyrus cried, tears spilling from his sockets.

The kid was frozen, knife falling to the ground. Sans mustered a smile—his last, no doubt.

He recalled the kid’s words from the first timeline— _in this world, it’s kill or be killed_. Well, Sans denied both choices. That was a world he refused to live in.

“i believe in the good end.”

There would be no kill or be killed. Not in this world. Not for Papyrus. Sans wouldn’t let that happen.

The child stared. Tears fell from their red eyes.

 _maybe…did i finally get through to them?_ Sans wondered.

“SANS!”

Sans cast one last look at Papyrus…and his pupils shrank. Behind Papyrus stood another Papyrus, this one ghostly and pale…as if they were in a glass box, just watching…

Just like Sans had been doing…until today…

The world fell to black. There was nothing more Sans could do.


	4. Reverse

**BEEP BEEP BEEP!**

The alarm went unnoticed. The tall skeleton sat in bed, just past noon that day, tears spilling from his sockets. He was muttering under his breath.

“not the end i was hoping for… i’ll just have to try again today…”

Papyrus reached up, scrubbing tears away. He pulled his legs to his chest and sighed.

“PAPYRUS! GET UP! YOU HAVE SENTRY DUTY TODAY!”

Papyrus sighed, closing his sockets. The last timeline flashed cruelly in his mind—Sans cut down in the snowy field by that murderous child. Papyrus couldn’t move to save him.

Just like every other time.

He frowned, lifting his skull to look out the window as Sans called again from downstairs. The sky was dark. Snow gently fell.

The same as every other RESET.

“i will stay determined…for sans’ sake…”

He pulled on his orange hoodie and went downstairs. Time to try again. To save his brother from his fate.

**Notes for the Chapter:**

> ...And that's how Underswap happens...
> 
> jk but really, thanks Youtube commenter for saying that...


End file.
